Fix scsi sysfs init so that a scsi_unregister can be called anytime after
a scsi_register.
- Create scsi_sysfs_init_host function and call from
scsi_register.

 drivers/scsi/hosts.c      |    4 ++--
 drivers/scsi/scsi_priv.h  |    1 +
 drivers/scsi/scsi_sysfs.c |   25 ++++++++++++++++---------
 3 files changed, 19 insertions(+), 11 deletions(-)